Whether you’re jetting to Aruba or vacationing in Vail, winter travel can take a toll on your health—and few things can ransack a holiday more quickly than debilitating stomach cramps or a case of the flu.
Because we tend to eat less healthy foods and spend less time in the sun, experts say immune systems are already weaker during winter, making us more prone to illness and infection. Throwing travel into the mix—the stress, the germ-infested shuttle buses, the unfamiliar food—can further increase the chances of getting sick.

Arm yourself against winter-vacation ailments by packing these eight essentials:

1. Reusable water bottle. The immune system requires fluids to fire at full tilt. “Water consumption is especially important during winter, because it’s typically dry, cold and tough to stay hydrated—unlike summer, when people have a natural desire to drink to cool down,” says Melissa Wood, ND, a wellness coach in San Antonio, Texas. “When traveling, people are busy and even more prone to forget to drink water.” Since water isn’t always accessible on the go—and drinking fountains often spout tap water that has contaminants such as chlorine and fluoride, Wood says—fill a few reusable, non-plastic (or BPA-free plastic) bottles with purified water before you leave home and tote them wherever you go.

2. Healthy snacks. “For many, wintertime means eating massive amounts of sugar and dairy, which stress the immune system,” Wood says. “While you’re on the road, easy-to-pack, healthy snacks like grapes, apple slices, organic peanut-butter packets and raw, unsalted almonds and pecans can help keep your body on track.” Wood suggests skipping dried fruit, because it doesn’t contain water and is often dried using sulfur dioxide, a chemical that can trigger allergic reactions.

3. Natural hand sanitizer or wipes. Germs run rampant in airports, aboard planes and at crowded ski chalets—just think how many mitten-clad kids wipe their noses before grabbing railings and pushing open doors. Experts agree that washing hands with soap and water is your best defense against germs, but sanitizing sprays and wipes offer a viable second option.

Look for products containing essential oils such as cinnamon, clove, lemon and rosemary, which have antibacterial effects, according to research published in BMC Complementary and Alternative Medicine in 2006. And avoid sanitizers with commonchemical antibacterials such as triclosan, which can disrupt hormones and foster bacterial resistance. For this reason, it’s also wise not to overdue it with the hand sanitizing.

4. Supplements. Traveling makes it tough to find food with adequate immune-boosting nutrients, so supplements can pick up the slack and help keep you healthy. Jacob Teitelbaum, MD, author of From Fatigued to Fantastic (Avery Trade, 2007) and the “Cures A to Z” smartphone app, suggests taking 500 mg of vitamin C and 1,000 to 2,000 IU of vitamin D—which many people already lack during winter—per day to help stave off sickness. Also consider taking probiotics to not only support the immune system but also to protect digestive health.

In the book Boost Your Health With Bacteria (Active Interest Media, 2009), coauthors Fred Pescatore, MD, and Karolyn A. Gazella explain that more than 70 percent of our immune system cells live in the digestive tract.
“It’s critical to keep the digestive system healthy by taking a quality probiotic supplement, especially when traveling, because we can be exposed to harmful bacteria in food and water,” they explain. For easy travel, they recommend a probiotic supplement that doesn’t need to be refrigerated and is packaged in a dark bottle or blister packed to maintain effectiveness.

5. Ginger. If swaying gondolas or turbulent airplanes make you queasy, try chomping on fresh ginger or taking powdered-ginger capsules 30 to 60 minutes in advance to help preempt nausea and vomiting. Ginger has long been used to prevent and treat motion sickness (a 1988 Danish study of 80 sailors showed one-gram capsules worked better than placebo)—but experts haven’t pinpointed an exact mechanism. Wood says to steer clear of ginger candy, which can be packed with sugar or artificial sweeteners.

6. Natural sleep aid. Strange beds and unfamiliar noises can keep you from catching the 7.5 to eight hours of nightly rest that Teitelbaum insists most of us need to stay healthy. He says taking either 5 to 6 mg of melatonin or 150 to 250 mg of magnesium before bed can relax your body and mind to help you sleep. Melatonin also quells post-supper acid reflux, while magnesium relieves sore muscles, he adds.

7. Zinc lozenges. In case a cold or cough hits, have lozenges on hand to start popping immediately. Several studies, including a large 2011 meta-analysis published in Cochrane Database Systematic Review, show that zinc can cut the duration of upper-respiratory infections and make their symptoms less severe. Teitelbaum says zinc acetate, specifically, jump starts the immune system by mimicking the thymic hormone, so suck on four 20 mg lozenges per day.

8. Lavender essential oil. Action-packed trips can be stressful, but they shouldn’t leave you needing a vacation from your vacation. Wood suggests packing a bottle of pure lavender essential oil—not a chemically processed product—to abate anxiety and also aid sleep. “The bottle should read 100% pure essential oil and then Lavender, followed by the botanical name, Lavandula angustifolia,” Wood says. “When feeling stressed, put a drop or two on your hands, rub them together, cup your nose and inhale deeply for about a minute. Rubbing the oil on your chest or the back of your neck will often induce peaceful sleep.”